This invention relates generally to the navigation of a moving vehicle. In particular, this invention relates to a method and system of generating instructions for navigating the vehicle from a route generator.
Currently it is possible to navigate a vehicle, such as a car, using a database onboard the car that includes directions and coordinates for various locations. For example, the database may include existing directions and coordinates for the entire United States. Such a navigation system is sometimes called an autonomous navigation system.
In existing autonomous navigation systems, the directions for navigating the vehicle are generated by a processor, which is also on board the vehicle. The processor accesses the database and calculates directions based on the current location of the vehicle and the intended destination. Autonomous navigation systems are typically very expensive. Additionally, these autonomous systems become easily outdated as the coordinates and locations and points of interest stored in the database become outdated.
One alternative to autonomous navigation systems is to communicate with a server that can calculate a navigation route and transmit it to the vehicle. Typically, in such a server-based system, the current location of the vehicle is determined by the server using Global Positioning Systems and software. Dead reckoning systems such as gyroscopes or the use of vehicle speed pulses may also be used to help determine the current location of the vehicle. The destination is also indicated to the server, for example, by user-input. Then, the server generates a route based on these two points.
This server-based process may be very time consuming. Sometimes, the process of downloading the maneuver list from the vehicle""s current location to the destination may take a significant amount of time if the maneuver list is extensive. This may result in missed maneuvers or invalid routes as the vehicle continues beyond the original location upon which the maneuver lists were based. For example, a vehicle may pass the first maneuver before the instruction to navigate the first maneuver is downloaded. Moreover, current server-based navigation systems do not provide off-route detection, i.e. an indication that the vehicle has gone off the route indicated by the maneuver list. Additionally, current server-based navigation systems do not provide off-route correction. That is, because the database is not on board, there is a time lag between the time when a vehicle goes off-route and when the vehicle receives new maneuver instructions. This time lag may occur, for example, because the vehicle has to send a new request for a corrected route to the server based on a new current location.
It would be desirable therefore to provide a method for generating instructions for navigating a moving vehicle that overcomes the above.
One aspect of the present invention provides a method of generating navigation instructions for a vehicle. A destination is requested at the vehicle and forwarded to a route generation application. At least one preliminary maneuver is calculated based on a current location of the vehicle and the destination. The preliminary maneuver is transmitted from the route generation application to the vehicle and is executed at the vehicle. At least one remaining maneuver may be calculated while the vehicle executes the at least one preliminary maneuver. The remaining maneuver may be transmitted to the vehicle and executed. The at least one preliminary maneuver may comprise three maneuvers. All remaining maneuvers may also be calculated while the vehicle executes the at least one preliminary maneuver. All remaining maneuvers may be transmitted to the vehicle.
Another aspect of the present invention provides a navigation system including at least one route generation application wherein the route generation application calculates at least one preliminary maneuver before calculating any remaining maneuvers, at least one service manager for transmitting the at least one preliminary maneuver to a vehicle operatively adapted to execute the at least one preliminary maneuver. The system may also include at least one database in communication with the route generation application comprising location coordinates. The system may also include at least one navigation interface in communication with the vehicle operatively adapted to receive the at least one preliminary maneuver. The system may also include at least one communication interface in communication with the vehicle operatively adapted to transmit location information from the vehicle.
Another aspect of the present invention provides computer usable medium including a program for generating navigation instructions for a vehicle including computer program code that requests a destination at the vehicle, computer program code that forwards the destination to a route generation application, computer program code that calculates at least one preliminary maneuver based on a current location of the vehicle and the destination, computer program code that transmits the at least one preliminary maneuver from the route generation application to the vehicle and computer program code that executes the at least one preliminary maneuver at the vehicle. The program may also include computer program code that receives the at least one preliminary maneuver at the vehicle. The program may also include computer program code that calculates at least one remaining maneuver while the vehicle executes the at least one preliminary maneuver. The program may also include computer program code that transmits the at least one remaining maneuver to the vehicle and computer program code that executes the at least one remaining maneuver at the vehicle. The program may also include computer program code that receives the at least one remaining maneuver at the vehicle. The program may also include computer program code that calculates all remaining maneuvers while the vehicle executes the at least one preliminary maneuver and computer program code that transmits all remaining maneuvers at the vehicle. The program may also include computer program code that executes all remaining maneuvers at the vehicle.
Another aspect of the present invention provides a system for generating navigation instructions for a vehicle. The system includes means for requesting a destination at the vehicle and means for forwarding the destination to a route generation application. The system may also include means for calculating at least one preliminary maneuver based on a current location of the vehicle and the destination, means for transmitting the at least one preliminary maneuver from the route generation application to the vehicle and means for executing the at least one preliminary maneuver at the vehicle.
The foregoing and other features and advantages of the invention will become further apparent from the following detailed description of the presently preferred embodiments, read in conjunction with the accompanying drawings. The detailed description and drawings are merely illustrative of the invention rather than limiting, the scope of the invention being defined by the appended claims and equivalents thereof.